~~NOTOC~~
====== Examples : Pair Potentials ======

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//**Warning:**//
This is an example potential. Please do NOT use it for any real simulations!
</wrap>

This is a simple pair potential that can be used in //potfit//. 
The analytic function used is a Lennard-Jones.

It makes use of the **smooth cutoff** feature.

<code potfit Example_Pair_3>
#F 0 3
#T PAIR
#I 0 0 0
#E

# Enable the smooth cutoff with _sc
type lj_sc
cutoff 6.0
epsilon 0.10    0.00    1.00
sigma   2.50    1.00    4.00
# One additional parameter for the smooth cutoff function
h       1.00    0.50    2.00

# Enable the smooth cutoff with _sc
type lj_sc
cutoff 6.0
epsilon 0.10    0.00    1.00
sigma   2.50    1.00    4.00
# One additional parameter for the smooth cutoff function
h       1.00    0.50    2.00

# No smooth cutoff
type lj
cutoff 6.0
epsilon 0.10    0.00    1.00
sigma   2.50    1.00    4.00
</code>

To enable the smooth cutoff for a potential, the string ''_sc'' has to be appended to the identifier, 
e.g. ''lj_sc''. This increases the number of parameters for this potential by one. The cutoff 
parameter is added at the end of the parameter table and usually called ''h''.

The smooth cutoff can be enabled for each potential individually.

==== makeapot ====

The example potential can be generated with the following ''makeapot'' command:

  makeapot -n 2 -i pair -f 2*lj_sc lj